Determination of a fire guidance solution of an artillery weapon

ABSTRACT

A method for determining a fire guidance solution of an artillery weapon in indirect ballistic fire to hit a target. A changing weapon position of the weapon and a target position of the target are taken into consideration as geographical position data.

This application is a national stage filing of International (PCT)Application No. PCT/DE2021/100806, corresponding to InternationalPublication No. WO 2022/083822 filed on Oct. 6, 2021, which in turnclaims priority to German Application No. 10 2020 127 430.0 filed onOct. 19, 2020. The entire contents of both of those applications arehereby incorporated by reference.

The present disclosure relates to methods for determining a fire controlsolution of an artillery weapon in indirect ballistic fire to hit atarget. Further advantages are a fire control system for determining afire control solution of an artillery weapon in indirect ballistic fireto hit a target and an artillery weapon system with an artillery weaponfor combating a target in indirect ballistic fire.

BACKGROUND

In order to hit a target with a ballistic projectile of a weaponreliably and precisely over long distances, as is common in the use ofweapon systems with large-caliber weapons, and thus to be able to fightsuccessfully, it is necessary to describe the movement of the projectiledepending on the orientation of the weapon. For this purpose, a firecontrol equation is used, which, following its solution, provides a firecontrol solution according to which the weapon can be aimed in order tobe able to combat the target. To solve the fire control equation, a firecontrol system is usually used, which enables an automated determinationof the fire control solution.

Among weapon systems with large-caliber weapons, which are aimed usingfire control solutions, artillery weapon systems have one of the mostimportant support functions in modern military conflicts. As flexiblydeployable systems, these can be used both offensively and defensively.The precision of the artillery weapons of such artillery weapon systemshas increased significantly in the past. Modern weapon systems enablethe use of state-of-the-art ammunition and improved fire controltechnology to achieve high accuracy due to their high manufacturingquality. Above all, this makes it possible to minimize collateral damageand avoid endangering one's own or allied forces.

In contrast to direct-firing weapons, combating a target with artilleryweapons takes place in indirect ballistic fire. In this case, theballistic projectile is fired by the artillery weapon in the lower orupper angle group, i.e. with an elevation angle of up to 65°, which isalso referred to as steep fire. While in direct-firing weapons there isa direct line of sight between the weapon and the target, so that thetarget can be seen from the weapon and detected directly relative to itin the coordinate system of the direct-firing weapon, such a direct lineof sight is not present with artillery weapons. Looking from theartillery weapon, the target is rather obscured by visual obstacles ordue to the great distance by the curvature of the earth. In connectionwith artillery weapons, therefore, the term “non-line-of-sight” is alsoused.

With the current artillery weapons, in a stationary firing position,i.e. from a non-changing weapon position, it is only possible todetermine a fire control solution to fire at an equally static target atits target position. Assuming the stationary firing position requires aconsiderable amount of time for the transition from moving tostationary, unlashing and aiming the weapon, firing, resuming thetransport position, lashing down and finally resuming the journey.Throughout this process, the weapon itself forms a simple static target.The artillery weapon and its crew are therefore exposed to the threat ofreturn enemy fire, significantly reducing its survivability.

SUMMARY

An advantage of the present disclosure is therefore to increase thesurvivability of the artillery weapon and its operating crew, inparticular during a fire fight in which the weapon shoots at a targetand is itself exposed to return fire.

This can be achieved with a method of the type mentioned above by takinginto account a changing weapon position of the weapon and a targetposition of the target as geographical position data.

By taking into account the changing weapon position of the weapon andthe target position as geographic position data, it is possible to hitthe target as the weapon moves in the terrain, thus changing the weaponposition. This can also maximize the mobility of the weapon during afirefight and increase survivability, as a moving weapon is harder toreconnoiter and hit. The risk of a hit by enemy return fire is reducedbecause the protective moment of the weapon's own movement can bemaintained even during firing. Such a possibility of indirect ballisticfire with an artillery weapon while moving has so far been classified inexpert circles as technically unfeasible. By taking into account thechanging weapon position as well as the target position as geographicalposition data, which are not affected by the positions and locations ofthe weapon and the target relative to each other, it is possible todetermine a fire control solution despite the—movement of the weapon andthe lack of a direct line of sight connecting the weapon and the target.

The fire control solution can be determined while taking into accountthe changing weapon position and the target position of the target asgeographic position data.

The geographical position data can be detected in the form ofgeographical coordinates, for example in the form of latitude andlongitude.

The fire control solution can be determined during movement of theweapon. The preparation of indirect firing while moving can also be donein this way while moving. The ability of indirect firing while movingcan lead to a reduction in the reaction time between the receipt of afiring task via a command system and implementation of the firing taskin the context of an adapted firing command after the determination ofthe fire control solution in combination with a minimized vulnerabilityof the weapon.

At least one absolute parameter independent of the relative positionand/or relative location of the weapon and the target can be taken intoaccount. By taking into account an absolute parameter, it is possible totake into account parameters which influence the fire control solutionand which are independent of the relative position and/or relativelocation of the weapon and the target to each other when determining thefire control solution. The at least one absolute—parameter can bedetermined in an absolute coordinate system which is not dependent onthe position of the weapon and/or the target or can be determined as avalue on an absolute scale. Such an absolute parameter can thus beindependent of the relative position of the weapon and the target toeach other and/or of the relative location of the weapon and the targetto each other, i.e. a change in the position and/or location of theweapon in relation to the target just as little effect on it as a changein the position and/or location of the target in relation to the weapon.

In this context, it may be advantageous if an absolute terrain height ofthe weapon position, an absolute terrain height of the target position,an absolute time and/or an absolute system parameter of the weapon istaken into account as absolute parameter. The absolute terrain height ofthe weapon position and/or the target position can be determined as theheight difference of the weapon position or the target position comparedto a zero level. To determine the absolute terrain height, for example,topographic map material and/or topographical measuring instruments canbe used. In particular, the same zero level may be used when taking intoaccount the absolute terrain height of the weapon and the absoluteterrain height of the target position. By taking into account anabsolute time, a calculation of parameters flowing into the fire controlequation, which are determined at different times, at differentlocations and/or by different system components, can be carried out in aconsistent time relationship. The absolute time can serve as a timestandard, which is referred to in the determination of the otherparameters included in the fire control equation. In contrast todirect-firing weapons, where transmission and detection times arenegligible due to the direct line of sight and the detection at thespeed of light, the long distances in indirect ballistic fire ofartillery weapons can cause considerable transmission and detectiontimes. The influence of detection times and/or transmission times can betaken into account by means of the absolute time. Parameters existing atthe same time, but present at different times due to the detectionand/or transmission times, can be synchronized with each other by meansof the absolute time and can be used as synchronous parameters fordetermining the fire control solution. The absolute time can be takeninto account as a time stamp for determining the parameters, especiallyin decentralized system components. The absolute temperature of thepropellant, the shape of the projectile, the weight of the projectile,the caliber of the weapon, the rifling profile of the weapon and/or thespin of the weapon can be taken into account as absolute systemparameters of the weapon, for example.

In a development, the motion dynamics of the weapon and the motiondynamics of the target, in particular in absolute coordinates, are takeninto account. By taking into account the motion dynamics of the weaponand of the target, a fire control solution for hitting a moving targetwith a moving artillery weapon with indirect ballistic fire can bedetermined. The consideration of the motion dynamics makes it possible,in addition to constant, rectilinear movements of the weapon and/or thetarget, to take into account changes in the speed and direction ofmovement of the weapon and/or of the target. As limiting cases in whichthe speed of movement drops to zero, the method can also determine afire control solution for a moving artillery weapon to hit a stationarytarget, for a stationary artillery weapon to hit a moving target, andfor a stationary artillery weapon to hit a stationary target. With thismethod, the functionality of the known determination methods of a firecontrol solution can be covered, so that this method can not onlysupplement known determination methods but can completely replace them.

By taking into account the motion dynamics of the weapon, the futureweapon position that the weapon occupies at the time when a firedprojectile leaves the weapon can be determined. By taking into accountthe motion dynamics of the target, a future target position, which thetarget is likely to occupy when the projectile hits, can be anticipated.To anticipate the future target position, the movement of the target canbe extrapolated from the previously recorded motion dynamics of thetarget. By taking into account the motion dynamics in absolutecoordinates, they can be taken into account independently of therelative position and/or location of the weapon and the target inrelation to each other. With the absolute coordinates, the motiondynamics of the weapon and the motion dynamics of the target can betaken into account without being influenced by a change in the targetposition or the weapon position. The motion dynamics of the weapon andthe motion dynamics of the target can each be the movement behavior, inparticular the totality of the previously detected movements of theweapon or the target.

In this context, it may be advantageous if the motion dynamics aredetected in indirectly referenced coordinate systems. The motiondynamics recorded in indirectly referenced coordinate systems can berelated to each other without the coordinate system in which a motiondynamics is detected being directly referenced to the coordinate systemin which the other motion dynamics is detected. Since there is no lineof sight between the weapon and the target in the case of indirectballistic fire, the coordinate systems of the weapon and the targetcannot be directly referenced to each other. By indirectly referencingthe coordinate systems via one or more other coordinate systems, themotion dynamics recorded in different coordinate systems can also berelated to each other without a direct line of sight, in particular inabsolute coordinates.

When referencing each other, two coordinate systems can be set inrelation to each other. Indirect referencing allows two, especiallymoving, coordinate systems to be related to each other without therebeing a direct line of sight between them.

A further embodiment provides that a detection system is used to detectthe target. The detection system can also allow detection of the targetwithout a direct line of sight between the weapon and the target. Thedetection system may be a separate system from the weapon and inparticular independent of the weapon, such as a satellite, a drone, aUAV, an unmanned ground vehicle, an observation post, a vehicle-basedtarget detection system and/or an infantry target detection system. Withthe detection system, the target and in particular the target positionrelative to the detection system can be acquired from a coordinatesystem bound to the detection system. To detect the target, thedetection system may use one or more detection signals. The detectionsignal can be, for example, radar radiation reflected by the target,infrared radiation emitted by the target or light reflected by thetarget, with which the detection system can detect the target.

The motion dynamics of the detection system can be taken into accountwhen determining the fire control solution.

Furthermore, it may be advantageous if an absolute detection systemposition of the detection system is used in indirect referencing of thecoordinate systems. Because the detection system position is differentfrom the weapon position, the target's coordinate system can bereferenced directly to the coordinate system of the detection systemlocated at the detection system position. The coordinate system of thedetection system located at the detection system position can in turn bereferenced directly or indirectly via further coordinate systems to thecoordinate system of the weapon. In this way, the coordinate system ofthe target can be indirectly referenced to the coordinate system of theweapon via the coordinate system of the detection system. Similarly, thecoordinate system of the weapon can be indirectly referenced to thecoordinate system of the target or the coordinate systems of the weaponand the target can be indirectly referenced to another coordinatesystem.

When referencing the coordinate systems, they can be related to eachother in such a way that the positions and directions detected in afirst coordinate system can be transformed into the other coordinatesystem without loss of information. For this purpose, several matchingpositions, in particular at least three, can be detected from bothcoordinate systems.

In an advantageous embodiment, the properties of the detection systemare taken into account. Properties of the detection system to be takeninto account may include, for example, the processing time fromreception to forwarding of a detection signal by the detection system tothe weapon, the transit time of the detection signal from the target tothe detection system, the transit time of a forwarded signal from thedetection system to the weapon, the movement of the detection systemand/or the motion dynamics of the detection system. By also taking intoaccount the properties of the detection system when determining the firecontrol solution, the accuracy in determining the fire control solutioncan be further improved.

In a further embodiment, at least one artillery-relevant influencingparameter is taken into account, in particular vibration influences ofthe weapon, vibration influences of a weapon carrier and/or a firingtime development. Artillery-relevant influencing parameters can have aninfluence on the internal ballistics and/or the external ballisticsduring indirect ballistic fire. The artillery-relevant influencingparameters can be described statistically, in particular the vibrationinfluences of the weapon and/or the vibration influences of the weaponcarrier. The weapon carrier can accommodate the weapon as such and canenable its movement in the terrain, wherein the weapon carrier may be achassis or an armored hull, for example. Together with the weapon, theweapon carrier forms part of a weapon system. During the change of theweapon position, both vibrations of the weapon carrier relative to thesurrounding terrain and vibrations of the weapon relative to the weaponcarrier can occur. Vibrations of the weapon as well as those of theweapon carrier can affect the fire control solution, wherein it can leadto both constructive and destructive interference of the respectivevibrations. By taking into account the vibration influences of theweapon and the vibration influences of the weapon carrier, theseinterferences can also be taken into account. The consideration of thefiring time development, which is the time offset between the ignitionof a propellant charge and the muzzle exit of a projectile driven bythis propellant charge from the muzzle of the weapon, the accelerationtime of the projectile can be taken into account. In addition to thepure acceleration time, the acceleration behavior of the projectile canalso be taken into account as another artillery-related influencingparameter.

In this context, it may be advantageous if the artillery-relevantinfluencing parameter, in particular its effect on the fire controlsolution, is extrapolated. By extrapolating, an indication of themagnitude of this influencing parameter in the future time relevant todetermining the fire control solution and in the immediate future can begained from the previous development of the at least oneartillery-relevant influencing parameter.

In an advantageous embodiment, at least one geographical interferenceparameter is taken into account for determining aninterference-contour-free projectile trajectory. In addition to thetopography of the terrain, i.e. the height profile of the earth'ssurface without vegetation and buildings, the geographical interferenceparameters may also include other natural or artificially constructedgeographical structures, such as vegetation or buildings. By determiningan interference-contour-free projectile trajectory when determining thefire control solution, it can be ensured that the projectile does notencounter any obstacles, in particular static obstacles, influencing theprojectile trajectory during its projectile trajectory from the weaponto the target.

In an advantageous embodiment, geographic interference parameters in thearea of the weapon position and in the area of the target position are,in particular exclusively, taken into account for determination of theinterference-contour-free projectile trajectory. In this way, aninterference-free launch angle of the projectile from the weapon and aninterference-free approach angle of the projectile to the targetposition can be ensured.

Furthermore, when determining the interference-contour-free projectiletrajectory, the distance between the weapon position and the targetposition, the projectile flight time and/or the motion dynamics of thetarget can be additionally taken into account.

Advantageously, terrain modeling between the weapon position and thetarget position is carried out, in particular continuously. Due to theterrain modeling, which in addition to the topology can also includegeographical interference parameters present in the terrain, a model ofthe terrain that reflects the real conditions can be accessed at anytime and for each weapon position. The terrain modeling can be performedhighly dynamically, so that a reliable terrain model can be providedeven with changes in the direction of movement and the speed of movementof the weapon and/or the target. For terrain modelling, map material ofone or more maps stored in a database can be used. The terrain modellingcan be carried out between the weapon position assumed at the time ofmodelling as a quasi-static firing position during the movement of theweapon and the current and/or extrapolated target position. By includingthe extrapolated target position in the terrain modeling, theinterference contour freedom of the projectile trajectory can be easilydetermined, since the end point of the projectile trajectory is theextrapolated target position at which the target is expected to be whenthe projectile hits. By superimposing the calculated projectiletrajectory with the terrain model, it can be easily determined whetherthere are geographical interference parameters in the projectiletrajectory. For this purpose, it can be checked whether the calculatedprojectile trajectory and the surface of the terrain model intersect atone or more points between the weapon position and the target position.

In an advantageous embodiment, at least one blocking parameter, inparticular a definable restricted area, is taken into account. By takinginto account at least one blocking parameter, a firing of the weapon, bywhich the projectile would pose an inadmissible security threat, can beprevented. In a particularly simple way, a restricted area into which aprojectile may not enter and/or in which a projectile may not strike canbe defined as a blocking parameter. A restricted area can be defined,for example, as an area around a civil protection facility, a hospital,a separate field camp or one's own units. If the consideration of atleast one blocking parameter shows that firing would lead to a violationof the blocking parameter, for example, a fire signal of the weapon canbe interrupted. A definable restricted area can be variable over timeand can move, for example, together with own units that are moving.

In this context, it may be advantageous if no fire control solution isoutput depending on the blocking parameter, in particular depending onthe situation and/or time. Without the output of a fire controlsolution, there can be no inadmissible firing of the weapon based onconsideration of at least one blocking parameter. The prevention of theoutput of a fire control solution can be carried out depending on theblocking parameter and or depending on the situation and/or time, sothat, for example, a blocking parameter is only valid with regard to atype of munition used, in a defined time window, from a defined point intime or up to a defined point in time.

In the case of a fire control system of the type mentioned above, it isproposed for achieving the above concept that it is set up to carry outthe method described above, resulting in the advantages described inconnection with the method.

The features described in connection with the method may also be usedindividually or in combination in the fire control system. This resultsin the same advantages that have already been described.

In an artillery weapon system of the type mentioned above, it isproposed for achieving the above concept that this has a fire controlsystem of the type described above, resulting in the advantagesdescribed in connection with the method and the fire control system.

According to an one embodiment, the artillery weapon system comprises adamped weapon carrier for reducing vibrations during motion dynamics, inparticular for filtering high-frequency vibrations. Vibration influenceson the fire control solution can be reduced by the damped weaponcarrier, whereby the accuracy of the artillery weapon system can beincreased during indirect ballistic firing while driving.

It may be further advantageous if the weapon system has a hydraulicand/or electrical compensation system for compensating for vibrations ofthe weapon while driving.

In a further embodiment, the weapon is supported relative to the weaponcarrier with an imbalance-compensated weapon support. Due to theimbalance-compensated weapon support, the dynamics of the directionalmovement of the weapon can be increased and faster combatting of thetarget can be enabled.

The weapon can be supported about 360° relative to the weapon carrier,in particular in a turret system. The weapon carrier may advantageouslyprovide a large contact area to reduce tilting movements resulting fromunevenness in the terrain and/or to enable firing of the weapon indifferent directions relative to the weapon carrier with no supportingsystem, in particular in a horizontal angular range of 360° around theweapon carrier.

BRIEF DESCRIPTION OF DRAWINGS

Further details and advantages of a method, a fire control system and anartillery weapon system will be explained below by way of example on thebasis of the exemplary embodiments schematically represented in thefigures. In the figures:

FIG. 1 shows schematically a direct firing weapon in a top view,

FIG. 2 shows schematically an indirect ballistic firing of an artilleryweapon in a top view,

FIG. 3 shows schematically taking into account interference parameterswhen determining a fire control solution, and

FIG. 4 shows schematically taking into account a blocking parameter whendetermining a fire control solution.

DETAILED DESCRIPTION

In order to hit a target 5 with a ballistic projectile of the weapon 2of a weapon system 1, it is necessary to solve the so-called firecontrol equation in order to obtain a fire control solution. With directfiring weapons 1, this is no particular challenge even for a weapon 2 ona moving weapon carrier 3, so that the fire control solution can also bedetermined for a moving weapon 2. As a result, the direct firing weapon2 achieves good survivability, since the protective moment of theweapon's 2 own movement can be maintained even during shooting. In thecase of indirectly firing ballistic weapons 2, however, such firingwhile moving is not yet possible, which is reflected in thesurvivability of such indirectly firing artillery weapons 2.

As shown in FIG. 1 , there is a direct line of sight 7 between a directfiring weapon 2 and the target 5 to be hit. Without any particulardifficulties, the direct-firing weapon 2 can already be roughly aimed atthe target 5 along a direct line of sight 7. To determine the firecontrol solution, the movement of the target 5 in the target coordinatesystem K5 can be easily detected from the weapon 2 with a direct line ofsight 7 to the target 5 directly in the coordinate system K2 of theweapon 2 and used to determine the fire control solution. In such adirect firing weapon 2, the position and movement of the target 5relative to the weapon 2 are determined directly and as such relativepositions and movements are also taken into account in determining thefire control solution.

Due to the comparatively small distances and the direct line of sight 7between the weapon 2 and the target 5 during direct firing, which ischaracterized by a flat projectile trajectory, an error between theposition of the target 5 detected by the weapon 2 and the actualposition of the target 5 results solely from the time that the lightneeds to travel the distance between the target 5 and the weapon 2. Dueto the comparatively short distance and the very high speed of light,this time lag is negligibly small in direct firing.

During the indirect ballistic firing shown in FIG. 2 , however, the firecontrol solution cannot be determined as easily as for direct firing.During indirect ballistic firing, the distance between the artilleryweapon 2 and the target 5 to be hit is significantly greater than in thecase of a direct firing weapon, so that there is no direct line of sightbetween the weapon 2 and the target 5. As indicated in FIG. 2 , which isnot to scale, the line of sight 7 of the artillery weapon 2 is ratherinterrupted by an interference parameter 12. This interference parameter12 is indicated in FIG. 2 as a terrain height, but due to the very longdistances can also be caused by the curvature of the earth as such. Dueto the lack of a direct line of sight between the weapon 2 and thetarget 5, the coordinate systems K2, K5 can no longer be related to eachother, so that there are two independent coordinate systems for theweapon 2 and for the target 5.

In order to be able to determine a fire control solution under theseconditions in order to be able to hit the target 5 with the artilleryweapon 2, the changing weapon position P2 of the weapon 2 and the targetposition P5 of the target 5 are taken into account as geographicposition data with the method according to one embodiment. Both theposition of the target 5 and the constantly changing weapon position P2during the movement of the weapon system 1—indicated by the black arrowarranged on the weapon carrier 3—are indicated as geographical positionson the earth's surface. This indication can be made, for example,according to the respective longitude and latitude, so that these areconsidered for a weapon position P2 and the target position P5 asgeographic position data in an absolute coordinate system KA, which isnot affected by the respective position of the weapon 2 and the target 5relative to each other.

In addition to the weapon position P2 and the target position P5, therespective motion dynamics of the weapon 2 and target 5 can also betaken into account when determining the fire control solution. Thesemotion dynamics can also be taken into account when determining the firecontrol solution in an absolute coordinate system KA, which can be, forexample, the same coordinate system as has already been used fordetermining the geographic position data.

However, in order to be able to take the motion dynamics into accountwhen determining the fire control solution, they must first be detected.The movement of the target 5 takes place in the coordinate system K5,while the motion dynamics of the weapon 2 take place in the weapon's owncoordinate system K2. However, in order to be able to detect the motiondynamics of the weapon 2 and the target 5 in relation to each other, inorder to then transfer them to an absolute coordinate system KA and takethem into account when determining the fire control solution, thecoordinate systems K2 and K5 must be referenced to each other, i.e.related to each other. This can be carried out by means of a detectionsystem 6 independent of the weapon 2, with which the target 5 can bedetected. By means of this detection system 6, indirect referencing ofthe coordinate systems K2, K5 to each other can take place, even withoutan existing direct line of sight between the weapon 2 and the target 5.This indirect referencing relates the two moving coordinate systems K2,K5 to each other. In this way, it is possible to transform the motiondynamics of the target 5 detected in the coordinate system K5 with theindirect reference to the coordinate system K2 of the weapon 2 and thegeographical position of the weapon 2, for example more easilydetectable by means of a weapon's own GPS system, into an absolutecoordinate system KA. This motion dynamics of the target 5 transformedinto the absolute coordinate system KA can then be taken into accountwhen determining the fire control solution.

Since vibrations of both the weapon carrier 3 and the weapon 2 relativeto the weapon carrier 3 can occur while the weapon system 1 is moving inthe terrain, the influences of these vibrations as artillery-relevantinfluencing parameters in addition to the classic parameters for firingwhile moving, such as the target distance, the wind and the airpressure, can be considered as additional statistical parameters whendetermining the fire control solution of the weapon 2. In this case,these vibration influences of the weapon 2 and/or the weapon carrier 3as well as other artillery-relevant influencing parameters, such asfiring time development, can be calculated for the time of firing theweapon 2 by extrapolation. A terrain model, from which unevenness in theterrain and resulting vibration influences can also be predicted, canalso be incorporated in the prediction of these artillery-relevantinfluencing parameters and in particular of the vibration influences, inaddition to the past values of these influencing parameters.

In FIG. 3 , the indirect ballistic firing of an artillery weapon 2 of aweapon system 1 is shown schematically from a side view. This shows howthe topography of the terrain as an interference parameter 12 prevents adirect line of sight between the weapon system 1 and the target 5. Ascan also be seen, the terrain at the weapon position P2 has a differentterrain height than at the target position P5. To solve the fire controlequation, these different absolute terrain heights of the weaponposition P2 and the target position P5 are taken into account asabsolute parameters. The absolute terrain heights at the weapon positionP2 and the target position P5 can be specified against an absolutelydefined zero level, such as sea level, and as such, for example, aretaken from map information stored in a memory of the weapon system 1,based on the geographical position data of the weapon position P2 andthe target position P5.

A detection system 6 in the form of a satellite is shown above theweapon system 1 and the target 5 in FIG. 3 . From the detection systemposition P6, this detection system 6 can directly detect both the target5 at the target position P5 and the weapon system 1 at the weaponposition P2, i.e. there is a direct line of sight between the detectionsystem 6 and the target 5 or the weapon system 1.

From the detection system position P6, the detection system 6 can thusdetect the target 5 and its motion dynamics in the coordinate system K5in this way. This detection can be carried out, for example, using radarradiation reflected by the target 5, infrared radiation emitted by thetarget 5 or optically using light reflected by the target 5. Thereflected radar radiation, the emitted infrared radiation or thereflected light thus forms a detection signal which, despite propagationat the speed of light, requires a time t1 to travel the distance betweenthe target 5 and the detection system 6 and to be detected at thedetection system position P6.

In the detection system 6, this detection signal is processed before theprocessed signal is forwarded from the detection system 6 to the weaponsystem 1 at a time t2 after detection. The transmission of thisprocessed signal from the detection system 6 to the weapon system 1 inturn requires a certain time t3.

Since both the weapon 2 with the coordinate system K2 located at theweapon position P2 and the target 5 with the coordinate system K5located at the target position P5 can be detected from the detectionsystem 6, the detection system 6, with its detection system position P6determinable in the absolute coordinate system KA and the coordinatesystem K6 of the detection system 6 at this position, is suitable forindirect referencing of the coordinate systems K2 and K5. During thisindirect referencing by means of the detection system position P6, forexample, the coordinate system K5 with its origin at the target positionP5 can first be referenced from the detection system position P6 withthe original coordinate system K6 there. Subsequently, referencing ofthis detection system position P6 in the coordinate system K2 can becarried out from the weapon position P2. By means of the coordinatesystem K6 located at the detection system position P6, referencing ofthe coordinate system K2 and the coordinate system K5 at the vehicleposition P2 or the target position P5 can be carried out in this way,even without there having to be a direct line of sight between thetarget position P5 and the weapon position P2.

In order to further improve the accuracy in determining the fire controlsolution, properties of the detection system 6 are also taken intoaccount when determining the fire control solution. These properties maybe in particular the time t1 for acquiring the target 5 detectionsignals by the detection system 6, the time t3 for transmitting thedetection signals or the time t2 for processing the detection signal bythe detection system 6.

Although in FIG. 3 the detection system 6 is shown as a satellite, itmay also be other movable detection systems 6, such as a drone, a UAV ora reconnaissance aircraft. Such mobile detection systems 6 could have achanging detection system position P6. For such movable detectionsystems 6, the motion dynamics of the detection system 6 itself may alsobe included in the properties to be taken into account duringdetermination of the fire control solution.

A special challenge for land-based weapon systems 1 in the context ofindirect fire while moving is the solution of geographical challenges,which are reflected in particular in the form of geographic interferenceparameters 12-14. These geographic interference parameters 12-14 may be,for example, the topography 12 of the terrain or geographicalstructures, for example bridges or buildings as structures or the trees13, 14 shown as vegetation in FIG. 3 in the area of the weapon 2 and inthe area of the target 5. In order to avoid influencing the projectileduring its ballistic movement from the weapon 2 to the target 5, aprojectile trajectory 11 must be selected which is free of interferencecontours of these geographical interference parameters 12-14.Technically, the firing weapon system 1 must calculate the interferencecontour freedom of the projectile trajectory 11 to the target 5 on thebasis of geographical map material. This requires continuous, highlydynamic terrain modeling between the weapon system 1 at the weaponposition P2 and the target 5 at the target position P5, extrapolatedinto the future, especially taking into account the duration of theprojectile flight. As a result, on the one hand, an interference-freelaunch angle A relative to the horizontal at the weapon position P2,which is to be regarded as a quasi-static firing position at the momentof firing the projectile, and on the other hand, an interference-freeapproach angle B to the extrapolated target position P5, calculated inparticular taking into account the projectile flight time, can beensured.

In FIG. 3 , only the projectile trajectory 11 is free of an interferencecontour. The projectile trajectory 8 having a smaller launch angle A, onthe other hand, would already intersect the interfering contour 13 shownas a tree in the area of the weapon 2, so that a projectile on thisprojectile trajectory 8 would be disturbed by the interfering contour13. The projectile trajectory 9 intersects the profile of the terrain asan interference parameter 12, so that the projectile on this projectiletrajectory 9 would not reach the target 5 but would previously strike atthe height of the terrain. The projectile trajectory 10 also intersectsan interference parameter 14 in the form of a tree, whereby the approachangle B of the projectile would be disturbed. Of the projectiletrajectories 8 to 11 calculated for different fire control solutions andshown in FIG. 3 , taking into account the geographical interferenceparameters 12 to 14, only the projectile trajectory 11 would be free ofinterference and would thus be suitable for hitting the target 5 byindirect ballistic fire.

With the modification shown in FIG. 4 , in addition to the detectionsystem 6 in the form of a satellite, a further detection system 6 isprovided at the detection position P6, which may be, for example, afixed observation post from which the target 5 can be detected at thetarget position P5. The motion dynamics of the target 5, which is movingon a road 17, can be detected from this terrestrial observation post asa detection system 6.

The motion dynamics of the target 5 detected relative to the detectionsystem position P6 can be transmitted to a fire control system 4 of theweapon system 1 together with the absolute position of the detectionsystem 6, for example in the form of GPS positions in the absolutecoordinate system KA. Together with the map data stored in the firecontrol system 4, the motion dynamics of the target 5 in the absolutecoordinate system KA can be determined from the relative motion dynamicsof the target 5 together with the absolute detection system position P6for being taken into account when determining the fire control solution.During determination of the fire control solution by the fire controlsystem 4, the absolute motion dynamics of the weapon system 1 are thenalso incorporated in the absolute coordinate system KA, being detectedin the coordinate system K2 and transformed if necessary.

As well as the information from the ground-based detection system 6 atthe detection system position P6, the detection signals processed by thedetection system 6 in the form of a satellite can be forwarded to thefire control system 4 of the weapon system 1 for determining the firecontrol solution.

A defined restricted area 15 extends as a blocking parameter around anobject 16 to be protected, which is a hospital, for example. Aprojectile may not enter this restricted area 15 for safety reasons andmay not strike there, otherwise it would represent an inadmissiblesafety-related threat to the object 16. In order to comply with thisrestricted area 15, this is taken into account as a blocking parameterwhen determining the fire control solution. Should the target 5 continueto move along the road 17 towards the object 16 to be protected, so thatit enters the restricted area 15, no fire control solution would beoutput when determining the fire control solution as long as the target5 is in the restricted area 15, even if hitting the target 5 would bepossible without taking the blocking parameter into account.

With the help of the method, the fire control system 4 and the artilleryweapon system 1 described above, it is possible to increase thesurvivability of the artillery weapon 2 and its operating crew, inparticular even during a firefight in which the weapon 2 is firing at atarget 5 and is itself exposed to return fire.

REFERENCE SIGNS

-   -   1 Weapon system    -   2 Weapon    -   3 Weapon carrier    -   4 Fire control system    -   5 Target    -   6 Detection system    -   7 Line of sight    -   8-11 Projectile trajectory    -   12-14 Interference parameter    -   15 Restricted area    -   16 Object    -   17 Road    -   A Launch angle    -   B Approach angle    -   KA Absolute coordinate system    -   K2 Coordinate System    -   K5 Coordinate System    -   K6 Coordinate System    -   P2 Weapon position    -   P5 Target position    -   P6 Detection system position    -   t1 Time    -   t2 Time    -   t3 Time

Having described the invention in detail and by reference to the variousembodiments, it should be understood that modifications and variationsthereof are possible without departing from the scope of the claims ofthe present application.

What is claimed is:
 1. A method for determining a fire control solutionof an artillery weapon in indirect ballistic fire for hitting a target,wherein a changing weapon position of the weapon and a target positionof the target are taken into account as geographical position data. 2.The method as claimed in claim 1 wherein at least one absolute parameterindependent of the relative position and/or the relative location of theweapon and the target is taken into account.
 3. The method as claimed inclaim 2 wherein an absolute terrain height of the weapon position, anabsolute terrain height of the target position, an absolute time and/oran absolute system parameter of the weapon is taken into account asabsolute parameter.
 4. The method as claimed in claim 1 wherein a motiondynamic of the weapon and a motion dynamic of the target, in absolutecoordinates, are taken into account.
 5. The method as claimed in claim 4wherein the motion dynamics are detected in indirectly referencedcoordinate systems.
 6. The method as claimed in, claim 1 wherein adetection system is used to detect the target.
 7. The method as claimedin claim 6 wherein an absolute detection system position of thedetection system is used in the indirect referencing of the coordinatesystems.
 8. The method as claimed in claim 6, wherein the properties ofthe detection system are taken into account.
 9. The method as claimed inclaim 1 wherein at least one artillery-relevant influencing parameter,including vibration influences of the weapon, and/or vibrationinfluences of a weapon carrier and/or a firing time development, istaken into account.
 10. The method as claimed in claim 9 wherein theartillery-relevant influencing parameter, including its effect on thefire control solution, is extrapolated.
 11. The method as claimed inclaim 1 wherein at least one geographical interference parameter istaken into account for determining an interference-contour-freeprojectile trajectory.
 12. The method as claimed in claim 1 wherein acontinuous, terrain modeling between the weapon position and the targetposition is carried out.
 13. The method as claimed in claim 1 wherein atleast one blocking parameter, including a definable restricted area, istaken into account.
 14. The method as claimed in claim 13 whereindepending on the blocking parameter, including depending on thesituation and/or time, no fire control solution is output.
 15. A firecontrol system for determining a fire control solution of an artilleryweapon in indirect ballistic fire for hitting a target, wherein thesystem is set up for carrying out the method as claimed in claim
 1. 16.An artillery weapon system with an artillery weapon for combating atarget in indirect ballistic fire, including a fire control system asclaimed in claim
 15. 17. The artillery weapon system as claimed in claim16, further including a damped weapon carrier for reducing vibrationsduring motion dynamics, including for filtering high-frequencyvibrations.